1. Field of the Invention
The present invention relates to a picture image processing apparatus, and more particularly to a television picture image processing apparatus capable of preventing a picture quality of a television set from being degraded due to a poor contrast and brightness occurring in each corner of a television picture screen.
2. Description of the Prior Art
Conventionally, to enhance the picture quality of a TV set, a picture analysis and compensation technique has been employed, wherein chromatic aberration of an image-processed picture is detected in a facial or non-facial tone detector, for thereby deciding whether or not a flesh color is generated.
The compensation value of the detected color tone is selected in a normalizing circuit after the value of the color tone passes through a facial tone combiner for a facial color tone, and a non-facial combiner for a non-facial color tone.
The selected compensation value combined with a color offset value is fed back to an image processor for color compensation.
After detecting a ceiling or bottom value of Y-output, the compensated value may be fed back to a fuzzy logic processor, so that the picture quality can be enhanced by compensating the contrast or brightness thereof.
In the case of a color compensation, a flesh color is allocated in a region such as a R-Y or B-Y domain, and each value for the colors in the region is decided accordingly.
With regard to a contrast or brightness compensation, the value thereof is decided depending on a fuzzy logic operation.
However, the above-described conventional picture quality compensation has a disadvantage in that as a television picture screen increases in size, the picture quality is degraded in each corner of the TV picture screen.